People
with
aphantasia
exhibit
the
inability
to
voluntarily
generate
or
form
mental
imagery
in
their
minds.
Since
term
“aphantasia”
was
proposed
describe
this,
it
has
gained
increasing
attention
from
psychiatrists,
neuroscientists,
and
clinicians.
Previous
studies
have
mainly
focused
on
definition,
prevalence,
measurement
of
aphantasia,
its
impacts
individuals’
cognitive
emotional
processing,
theoretical
frameworks
synthesizing
existing
findings,
which
contributed
greatly
our
understanding
aphantasia.
However,
there
are
still
some
debates
regarding
conclusions
derived
research
theories
that
were
constructed
various
sources
evidence.
Building
upon
endeavors,
this
systematic
review
emphasizes
future
is
much
needed
refine
definition
diagnosis
strengthen
empirical
investigations
at
behavioral
neural
levels,
and,
more
importantly,
develop
update
theories.
These
multiple
lines
efforts
could
lead
a
deeper
further
guide
researchers
directions.
Consciousness and Cognition,
Год журнала:
2024,
Номер
120, С. 103679 - 103679
Опубликована: Апрель 1, 2024
Aphantasia
is
a
condition
that
often
characterized
as
the
impaired
ability
to
create
voluntary
mental
images.
assumed
selectively
affect
imagery
mainly
because
even
though
aphantasics
report
being
unable
visualize
something
at
will,
many
having
visual
dreams.
We
argue
this
common
characterization
of
aphantasia
incorrect.
Studies
on
are
not
clear
about
whether
they
assessing
or
involuntary
imagery,
but
some
studies
show
several
forms
also
affected
in
(including
dreams).
raise
problems
for
two
attempts
images
preserved
aphantasia.
In
addition,
we
results
study
afterimages
aphantasia,
which
suggest
these
tend
be
less
intense
than
controls.
Involuntary
treated
unitary
kind
either
present
absent
approach
mistaken
and
should
look
different
types
case
by
case.
Doing
so
reveals
no
evidence
broader
deficit
forming
not,
more
appropriate.
Characterizing
volitional
likely
lead
researchers
give
incorrect
explanations
wrong
mechanisms
underlying
it.
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2023,
Номер
unknown
Опубликована: Июнь 14, 2023
Abstract
Most
of
us
effortlessly
describe
visual
objects,
whether
seen
or
remembered.
Yet,
around
4%
people
report
congenital
aphantasia:
they
struggle
to
visualize
objects
despite
being
able
their
appearance.
What
neural
mechanisms
create
this
disparity
between
subjective
experience
and
objective
performance?
Aphantasia
can
provide
novel
insights
into
conscious
processing
awareness.
We
used
ultra-high
field
7T
fMRI
establish
the
circuits
involved
in
mental
imagery
perception,
elucidate
associated
with
internally
generated
information
absence
aphantasia.
Ten
typical
imagers
10
aphantasic
individuals
performed
perceptual
tasks
five
domains:
object
shape,
color,
written
words,
faces,
spatial
relationships.
In
imagers,
activated
left-hemisphere
frontoparietal
areas,
relevant
domain-preferring
areas
ventral
temporal
cortex
partly
overlapping
a
domain-general
area
left
fusiform
gyrus
(the
Fusiform
Imagery
Node).
The
results
were
valid
for
each
individual
participant.
individuals,
similar
but
there
was
reduced
functional
connectivity
Node
areas.
Our
unveil
domain-specific
imagery,
disorganization
aphantasia,
support
general
hypothesis
that
-
perceived
imagined
depends
on
integrated
activity
high-level
networks.
NeuroImage,
Год журнала:
2025,
Номер
unknown, С. 121171 - 121171
Опубликована: Март 1, 2025
The
coordination
of
different
brain
regions
is
required
for
the
visual
imagery
complex
objects
(e.g.,
faces
and
places).
Short-range
connectivity
within
sensory
areas
necessary
to
construct
mental
image.
Long-range
between
control
re-instantiate
maintain
While
dynamic
changes
in
functional
are
expected
during
imagery,
it
unclear
whether
a
category-specific
network
exists
which
strength
spatial
destination
connections
vary
depending
on
target.
In
this
magnetoencephalography
study,
we
used
minimally
constrained
experimental
paradigm
wherein
categories
were
prompted
using
word
cues
only,
decoded
face
versus
place
based
their
underlying
patterns
as
estimated
from
covariance
across
regions.
A
subnetwork
analysis
further
disentangled
contribution
connections.
results
show
that
can
be
both
short-range
long-range
Overall,
imagined
object
distinguished
observed
network.
Notably,
estimates
rely
purely
endogenous
signals
suggesting
an
external
reference
not
elicit
such
dynamics.
Neuroscience of Consciousness,
Год журнала:
2025,
Номер
2025(1)
Опубликована: Янв. 1, 2025
Abstract
Visual
imagery
is
a
dynamic
process
recruiting
network
of
brain
regions.
We
used
electroencephalography
(EEG)
and
functional
magnetic
resonance
imaging
(fMRI)
fusion
to
investigate
the
dynamics
category
selective
in
medial
parietal
cortex
(MPC),
ventral
temporal
(VTC),
primary
visual
(V1).
Subjects
attended
separate
EEG
fMRI
sessions
where
they
created
mental
images
personally
familiar
people
place
stimuli.
The
contrast
comparing
replicated
previous
findings
category-selectivity
cortex.
In
addition,
greater
activity
for
places
was
found
lateral
memory
areas,
frontal
eye
fields,
inferior
sulcus,
intraparietal
sulcus.
contrast,
fusiform
face
area
right
posterior
superior
Using
multivariate
decoding
analysis
fMRI,
we
could
decode
individual
stimuli
within
preferred
VTC.
A
more
complex
pattern
emerged
MPC,
which
represented
information
that
not
restricted
category.
were
also
able
data.
EEG–fMRI
indicated
similar
timings
MPC
VTC
during
imagery.
However,
VTC,
higher
regions
an
early
time
window,
later
window.
correlations
V1
occurred
period,
possibly
reflecting
top-down
progression
from
category-selective
In
his
recent
book
Mental
imagery:
Philosophy,
psychology,
neuroscience
,
Nanay
presents
a
far‐reaching
empirically
grounded
account
of
mental
imagery.
This
commentary
focuses
on
Nanay's
proposal
that
individuals
with
aphantasia,
cognitive
norm
variant
characterized
by
an
absence
imagery
experience,
have
unconscious
Recent
empirical
findings
aphantasia
are
reviewed,
and
evidence
both
for
against
voluntary
involuntary
in
is
discussed
the
context
general
its
taxonomy.
It
argued
people
contrary
to
proposal,
do
not
possess
medRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2025,
Номер
unknown
Опубликована: Май 23, 2025
Visual
mental
imagery,
the
ability
to
volitionally
form
perceptual
representations
without
corresponding
external
stimuli,
allows
reliving
of
past
events,
solving
problems
and
imagining
future.
The
absence
visual
called
aphantasia,
has
recently
been
recognized
occur
in
about
1%
general
population
but
cause
is
uncertain.
By
studying
rare
cases
acquired
aphantasia
we
can
identify
regions
that
when
injured
loss
imagery.
We
analyzed
lesions,
identified
from
case
reports
by
systematic
review,
previously
studied
control
lesions
causing
other
neuropsychiatric
symptoms
(n=887).
network
brain
connected
each
lesion
location
was
computed
using
resting-state
functional
connectivity
healthy
subjects
(n=1000).
First,
tested
controls
fusiform
imagery
node
,
a
region
ventral
pathway
which
active
during
tasks.
Then,
performed
data-driven
analysis
assessing
whole
sensitive
(100%
overlap)
specific
(family-wise
error
p<0.05)
for
aphantasia.
Finally,
compared
our
activations
associated
with
12
lesion-induced
occurred
multiple
different
regions.
However,
100%
these
locations
were
functionally
left
gyrus,
termed
.
Connectivity
this
both
aligned
connections
Lesions
are
located
many
all
gyrus.
These
findings
support
hypothesis
key
involved
offers
clinical
insight
into
injury
likely
